Consolidated Condensed Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2020	82,705
Balance at Dec. 31, 2020	$ 827	$ 85,070	$ 534,436	$ 620,333
Net income	$ 0	0	18,006	18,006
Issuance of common stock from share-based payment arrangement exercises and vesting of performance unit awards (in shares)	70
Issuance of common stock from share-based payment arrangement exercises and vesting of performance unit awards	$ 1	160	0	161
Employee taxes paid in exchange for shares withheld	0	(547)	0	(547)
Share-based payment arrangement compensation expense	0	336	0	336
Dividends on common stock	$ 0	0	(3,311)	(3,311)
Balance (in shares) at Mar. 31, 2021	82,775
Balance at Mar. 31, 2021	$ 828	85,019	549,131	634,978
Balance (in shares) at Dec. 31, 2020	82,705
Balance at Dec. 31, 2020	$ 827	85,070	534,436	$ 620,333
Repurchase and retirement of common stock (in shares)				0
Balance (in shares) at Dec. 31, 2021	83,034
Balance at Dec. 31, 2021	$ 830	85,718	565,129	$ 651,677
Balance (in shares) at Mar. 31, 2021	82,775
Balance at Mar. 31, 2021	$ 828	85,019	549,131	634,978
Net income	$ 0	0	67,422	67,422
Issuance of common stock from share-based payment arrangement exercises and vesting of performance unit awards (in shares)	259
Issuance of common stock from share-based payment arrangement exercises and vesting of performance unit awards	$ 2	713	0	715
Employee taxes paid in exchange for shares withheld	0	(2,196)	0	(2,196)
Share-based payment arrangement compensation expense	0	2,182	0	2,182
Dividends on common stock	$ 0	0	(51,424)	(51,424)
Balance (in shares) at Dec. 31, 2021	83,034
Balance at Dec. 31, 2021	$ 830	85,718	565,129	651,677
Net income	0	0	27,533	27,533
Issuance of common stock from share-based payment arrangement exercises and vesting of performance unit awards	2	766	0	768
Employee taxes paid in exchange for shares withheld	0	(1,610)	0	(1,610)
Share-based payment arrangement compensation expense	0	369	0	369
Dividends on common stock	$ 0	0	(4,975)	$ (4,975)
Repurchase and retirement of common stock (in shares)	(1,307)			(1,300)
Repurchase and retirement of common stock	$ (13)	(24,987)	0	$ (25,000)
Balance (in shares) at Mar. 31, 2022	81,947
Balance at Mar. 31, 2022	$ 819	$ 60,256	$ 587,687	$ 648,762